Automatic cut-off for gas-service pipes.



N0. 575,5"). Patented June 4, I901.

G. S. FDLSOM. AUTOMATIC CUT-OFF FDR GAS SERVICE PIPES.

(Application filed. Nov. 10, 1897.)

2 Sheets-Sheet I,

(No Model.)

WITNESSES:

: Norms PETEH$ 00.. Mmoumovv WASHINOYON, o. c.

No. 675,510. Patented June 4 l90l. C. S. FULSOM.

AUTOMATIC CUT0FF FOR GAS SERVICE PIPES (Application filed Nov. 10,1807.) {No Model.) 2 $heets$heet 2 WITNESSES: "VENT R UhllllllllllSmarties a rnnir OFFICE;

CHARLES S. FOLSOM, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO RUUDMANUFACTURING COMPANY, OF CAMDEN, NEW' JERSEY.

AUTOMATlC CUT OFlF FUR GA$ SIERWCE PIPES,

fiPEOIFlOATION forming part of Letters Patent No. 675,510, dated June 4,1901.

Application filed November 10, 189 7. Serial No. 658,076. (No model.)

T (tZZ whom it may concern:

Be it known that 1, CHARLES S. FOLSOM, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a certain new anduseful Improvement in Automatic Cut-Offs for Gas-Service Pipes, of whichimprovement the following is a specification.

My invention is more particularly designed for application in connectionwith a Water heating apparatus in which the supply of gas to the burnersis regulated and controlled by a thermostat, but is equallyapplicableinconnection with gas heating apparatus of other descriptionsin whichregulation is effected by a thermostat.

The object of my invention is to provide simple, reliable, andinexpensive means by which communication from a gas-service pipe to aburner in a heating apparatus in which gas-supply is regulated by athermostat may be automatically cut off upon the extinguishment of theflame at the burner without interfering with the normal regulation ofsupply during the periods in which combustion is maintained at theburner.

The improvement claimed is hereinafter fully set forth.

In the accompanying drawings, Figure 1 is a vertical section through awater-heater with my improvement applied; Fig. 2, a similar section, onan enlarged scale, through the valve-casing of the same; Fig. 3, asection, on the same scale, through a portion of the valve-casing, takenat right angles to Fig. 2; Fig. 4,, a view similar to Fig. 1, showingthe cut-off valve as located in an independent casing; and Fig. 5, alongitudinal section through the cut-off-valve casing of Fig. 4.

The water heating apparatus to which my invention is herein shown asapplied, and which in and of itself is not claimed as of my invention,consists, essentially, of a coil of pipe 1, to the opposite ends ofwhich are connected a cold-water-inlet pipe and a hot-water-outlet pipe,which are not shown. The coil is heated by a series of main gas-burners4.- and a lighting or pilot burner 5, to which burners gas is suppliedby a service-pipe 6. The supply of gas to the main burners is controlledby a supply-valve 7 of the lift or puppet type, seating over a port 8 ina transverse partition 20, formed in a valve-casing 9, from which aninlet-pipe 10 leads to the several main burners t. An independentinlet-pipe 11 leads from a port or passage 3 in the valvecasing 9 to thepilot-burner 5. The total or partial opening and closure of thegas-supply valve 7 is regulated so as to supply a greater or lessquantity of gas to or to entirely out off gas from the main burners 4 bya thermo- 6o stat or thermal regulating device located in position to besubjected to the heat of the several burners and in the instance shownconsisting of an outer tube 12, forming part of the circuit for waterthrough the coil, an inner tube 18, formed of metal having acoinparatively high coefficient of expansion and fixed at one end, and arod 14;, which is formed of less-expansible metal than the tube 13 andbears at one end against a pivoted le- Ver 15. The lever 15 bearsagainst another pivoted lever 16, the free end of which bears against anut 17, which is adjustable upon the stem 18 of the gas-supply valve,and a closing-spring 19 bears on the supply-valve 7 5 with a constanttendency to bring the same to and hold it upon its seat, such tendencybeing counteracted by the contraction of the tube 13 under reduction oftemperature, which acting through the rod 14L and levers 8o 15 and 10moves the gas-supply valve 7 to a greater or less extent from its seat.

In water heating apparatus of the general character of that abovedescribed, as constructed prior to myinvention, the inlet-pipe 11 of thepilot-burner 5 is constantly in communication with the gas-service pipe6, and consequently it the flame at the pilot-burner should heaccidentally or carelessly eXtinguished, as by a temporary interruptionof the gas-supply or from any other cause, the thermostat would, byreason of the consequent reduction of temperature, open the gassupplyvalve 7, and upon the resumption of supply, it interrupted, gas wouldescape from 9 5 the main burners 4, as Well as from the pilotburner 5,and not being ignited bya flame at the pilot-burner, as provided for inthe normal operation of the apparatus, the escape of gas would, unlessfreely discharged through a tight flue, (which discharge cannot alwaysbe insured,) involve liability to explosion or gas-supply valve 7 ismade of slightly-increased length, and a cut-off valve 22, adapted tocontrol the supply-port 8 and to seat on the opposite side of thepartition 20 from the supply-valve 7, is fitted freely on the stem 18between a collar 23, fixed thereon, and a spring 24, which bears at oneend on the back of the cut-off valve and at the other on a nut 25,engaging a screw-thread on the stem, by which the tension of the springmay be adjusted as desired. WVashers 21 are preferably interposedbetween the collar 23 and the cut-off valve, by the removal of one ormore of'which and the location of one or more of which adjacent to thenut 25 the distance of the cutoff valve from the collar, andconsequently the distance through which the cut-off valve will movebefore closing the port 8, may be adjusted as desired. The cut-off valveis thus held up to the collar by the spring, and longitudinal movementof the valve-stem independently of the cut-off valve is permitted whenrequired. A washer-plate may he interposed between the nut and spring,if desired, to provide larger bearing-surface, and the nut may be heldin adjusted position by a lock-nut. The cut-off valve 22 is adjustedupon the valve-stem at such distance from the supply-valve 7 that thelatter may be raised from its seat by the thermostat sufficiently toeffect the maximum supply of gas to the burners which is required in thenormal operation of the apparatus without causing the valve-stem tocoincidently bring the cut-off valve 22 close enough to its seat on thepartition 20 to cut off or impede the flow of gas to the burners. Inorder to enable the operation of the apparatus to be readily reso medafter the cut-off valve has been seated, a bypass 28, controlled by acook or plug 29 and leading from the supply side of the partition 20 toa communication with the port 3 of the pilot-burner delivery-pipe, maybe cored in or connected to the valve-casing 9.

In the normal operation of a heating apparatus with my improvementapplied as above described the supply of gas to the bu rners isregulated by the thermostat in the manner heretofore practiced, thetraverse of the cut-off valve toward its seat being, as before stated,insufficient to affect the supply. When, however, the flame at thepilot-burner is extinguished, the resultant reduction of temperaturecauses the contraction of the tube 13, which acting through itsconnections in the manner normal to the apparatus on the valve-stem 18moves the supply-valve 7 farther from its seat and coincidently bringsthe cut-off valve 22 to its seat, thereby cutting off the supply of gasfrom the servicepipe to all the burners and preventing any escape of gasfrom the latter. Any further outward movement of the valve-stem 18 whichmay be effected by the thermostat after the cut-off valve has beenbrought to its seat is permitted without strain or injury to any of theparts by the cut-off valve being fitted, as before described, freely onthe stem, which moves through it after it has been seated as far as maybe due to the continuous action of the thermostat, the cut-off valvebeing held to its seat by the spring. When it is desired to relight thepilot-burner to resume the operation of the heater, the cut-off valvemay be opened by moving the valve-stem by hand by pressing on the lever16, which will allow the valve-stem to move sufficiently to open apassage for gas, or if a by-pass is provided the cook or plug thereofmay be opened.

Figs. 4 and 5 illustrate a form of my invention corresponding in alloperative features with that above described and differing therefromstructurally only in the particular that the cut-off valve 22 is fittedto seat in an independent valve-casing 30, interposed between-twosections of the service-pipe 6 on thesupply side of the supply-Valvecasing, and is connected with a valve-stem 31, which is moved indirection to open and close the cut-off valve, as required, by an arm32. The arm 32 is formed upon or fixed to the thermostat-lever 16, whichis connected to the supply-valve and projects in opposite direction fromthe pivot of said lever, so that closing movement shall be imparted tothe cutoff valve coincidently with the opening move ment of thesupply-valve, and vice versa. The relative lengths of the lever 16 andthe arm 32 are so proportioned that, as in the instance first described,the traverse of the supply-valve toward and from its seat which isrequired in the normal operation of the heater may be effected withoutcompletely closing the cut-off valve, and traverse of the cut-off-valvestem 31 independently of the cutoff valve after said valve has beenseated is provided for, as in the former instance, by connecting thecut-oif-valve stem to the cut-off valve with the capacity ofindependentmovement of the former. To this end a collar 33 is formed onthe inner end of the valve-stem and a cage or series of projections 34:,adapted to engage said collar, is formed on the back of the valve. Thecut-off valve is seated by a spring 35 and is held to its seat by saidspring, except when raised therefrom by the engagement of the collar onthe valvestem with the cage on the valve by outward movement of thevalve-stem. Upon the release of such engagement by the inward movementof the valve-stem coincident with a lift of the supply-valve greaterthan that required in the normal operation of the heater the cut-ofivalve is seated and held seated bythe spring, and any further inwardmovement of the valve-stem, due to the continued action of thethermostat, is effected Without imposing strain or pressure on thecut-off valve. A by-pass 28, extending from one side of the cut-offvalve to the other and controlled by a plug or cook 29, is preferablyprovided, as in the instance first described, to enable gas to besupplied to the pilot-burner 5 independently of the action of thethermostat for relighting the same after it has been extinguished, andin Fig. 4 such aby-pass is shown as connected directly to thevalve-casing 30.

I claim as my invention and desire to se cure by Letters Patent- 1. Thecombination, substantially as set forth, of a gas-burner, a gas-servicepipe leading thereto, a valve-easing in the service-line to the burner,a ported partition in said valvecasing, a stem working in saidvalve-casing, a supply-valve fixed on said stem and fitted to seat onone end of the partitionport, a cutoff valve fitted on said stem, withthe capacity of independent longitudinal movement on the stem, andadapted to seat on the other end of said port, a spring through which alimited degree of traverse of the valve-stem is imparted to the cut-offvalve, and a thermostat connected to and imparting longitudinal movementto the valve-stem.

2. The combination, substantially as set forth, of a main gas-burner, anindependent or pilot burner, a cut-off valve controlling the supply ofgas to the pilot-burner, a supplyvalve controlling the supply of gas tothe main burner, a thermostat, connections from the thermostat to thesupply and cut-oft valves whereby opening movement is imparted to one ofsaid valves and coincident closing movement to the other, and means forper-' mitting a partial traverse of the supply-valve Without coincidentmovement of the cut-off valve.

CHARLES S. FOLSOM.

Witnesses:

J. SNoWDnN BELL, W. L. MERWIN.

